stt1
Professional
I have a Grid Seeker which I have had in a shelf a long long time, I don't even recall anymore where it came from. And yes, this is original PCB, not bootleg. Has NO connectors for the cartridge.
Fault:
When it came in the player fire button 1 was jammed on - immediately when credited, the game would start and shooting continuously. Also sounds were turned to max. Checked the signal path from the button to the big SMD component right from the jamma-connector and it was ok. Decided that the SMD component must be busted.
Bought normal Taito F3 PCB 1-2 year later which had sound issues and that big SMD component was changed from it. After changing the SMD chip the fire button did not work at all, it's all off... Since that the board has been put away waiting some idea to come.
So, everything else seems to work (graphics, sounds, player 1 stick, player 2 controls...), but this player one fire button does not. I will give one more round of examination for this board next week (mainly measuring the obvious traces and check the SMD legs with microscope which I now have - which likely wont give anything new here...), but unless I find the problem it's maybe better to let this board go.
So, if I'm unable to find the actual issue, what would the price level for such faulty PCB?
Fault:
When it came in the player fire button 1 was jammed on - immediately when credited, the game would start and shooting continuously. Also sounds were turned to max. Checked the signal path from the button to the big SMD component right from the jamma-connector and it was ok. Decided that the SMD component must be busted.
Bought normal Taito F3 PCB 1-2 year later which had sound issues and that big SMD component was changed from it. After changing the SMD chip the fire button did not work at all, it's all off... Since that the board has been put away waiting some idea to come.
So, everything else seems to work (graphics, sounds, player 1 stick, player 2 controls...), but this player one fire button does not. I will give one more round of examination for this board next week (mainly measuring the obvious traces and check the SMD legs with microscope which I now have - which likely wont give anything new here...), but unless I find the problem it's maybe better to let this board go.
So, if I'm unable to find the actual issue, what would the price level for such faulty PCB?